Hummer 2008 H2 - Manual (Page 178)

Defogging and Defrosting
Fog on the inside of the windows is a result of high
humidity (moisture) condensing on the cool window
glass. This can be minimized if the climate control
system is used properly. There are two modes to
clear fog or frost from the windshield.
Use the mode up and down arrows to select the
defog or defrost modes.
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(Defog): The defog mode is used to clear the
windows of fog or moisture and warm the passengers.
This mode directs air to the windshield, floor outlets,
and side window vents. When this mode is selected,
the system turns off recirculation and runs the air
conditioning compressor unless the outside temperature
is close to freezing. The recirculation mode cannot
be selected while in the defog mode. Do not drive
the vehicle until all the windows are clear.
0
(Defrost): Press this button to remove fog or frost
from the windshield more quickly. This mode directs
a portion of the air to the windshield and side window
vents and some to the floor vents. In this mode, the
system will automatically force outside air into the
vehicle. The recirculation mode cannot be selected while
in the defrost mode. The air conditioning compressor
runs automatically in this setting, unless the outside
temperature is close to freezing. Do not drive the
vehicle until all the windows are clear.
Rear Window Defogger
The rear window defogger uses a warming grid to
remove fog from the rear window.
<
(Rear Window Defogger): Press this button to
turn on the rear window defogger. It will automatically
turn off several minutes after it has been activated.
The defogger can also be turned off by pressing
the button again or by turning off the engine. Do not
drive the vehicle until all the windows are clear.
If your vehicle has heated outside rearview mirrors,
the mirrors will heat to help clear fog or frost from the
surface of the mirror when the rear window defog
button is pressed.
Notice: Do not use a razor blade or sharp object
to clear the inside rear window. Do not adhere
anything to the defogger grid lines in the rear glass.
These actions may damage the rear defogger.
Repairs would not be covered by your warranty.
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